This invention relates to a toner cartridge or cassette for supplying toner to the developing device of an image forming apparatus such as an electrostatic copying apparatus or the like.
Generally, a toner cartridge has a hopper area for storing a predetermined supply of toner and is provided with a toner flow or outlet region disposed in the bottom area thereof. Removable closure or seal means is provided to open the toner flow or outlet region when and as desired to facilitate toner flow into an associated copy machine. The closures or seals typically employed include thin flexible strips, seal tape, shiftable shutters and the like.
Replacement toner cartridges are desirably first installed in a closed condition in an associated image forming apparatus. The closure or seal member may then be opened or removed to allow toner in the hopper area to flow outwardly from the cartridge into the image-forming apparatus for use. In some cases, the cartridge remains in place on the apparatus while in other cases the cartridge is immediately removed. This really is a function of the apparatus design and operational parameters.
In either situation, it is important to be able to re-close the toner flow or outlet region during cartridge removal to prevent unacceptable and undesired toner spills. That is, a small amount of residual toner may remain in the cartridge even though the cartridge may be considered empty from an operational point of view. Thus, it is highly desirable to have effective and reliable means to re-close the cartridge to avoid toner spillage during cartridge removal. Toner is comprised of very small particles which, if undesirably released, can create a dirty work environment and cause operational and quality difficulties in the image forming apparatus itself.
Some existing toner cartridges have toner flow or outlet openings which can be closed by a plate-like cover prior to removal of the cartridge. However, the covers are sometimes rather loose fitting so that some residual toner can still escape into the air and onto the imaging apparatus. Some other existing cartridges use selectively shiftable shutter mechanisms to open and close toner flow. There, however, it is oftentimes difficult for the user to determine whether the shutter is completely or partially open or closed before lifting or removing the toner cartridge from the image-forming apparatus. This, too, presents the potential for unknowingly spilling residual toner. Moreover, if the plate-like covers or shutters are dimensioned to be close fitting with the associated cartridge to prevent spillage, they may be very difficult to open and close. This, in turn, creates an entirely different set of problems.
Accordingly, it has been considered desirable to develop an improved toner cassette which would overcome the foregoing difficulties and others while providing better and more advantageous overall results.
The present invention relates to a toner cartridge or cassette having a louvered slide mechanism which may be selectively opened and closed for allowing or blocking toner flow therefrom. The present invention provides a mechanical arrangement for allowing the user to know when the cartridge is open or closed, and has the added advantage of providing a mechanical advantage over existing slide mechanisms to effect ease of opening and closing.
Current louvered slide mechanisms do not indicate if the cartridge is open (allowing toner to drop from the bottom) or closed. One aspect of the invention is to indicate to the end user that the cartridge is fully open or closed. Also, existing toner cartridges have slides and slide mechanisms which are oftentimes difficult to move by hand pulling or pushing. The present invention provides an eccentric knob or cam which provides a mechanical advantage to the opening and closing process.
More particularly, the present invention relates to a toner cartridge having a hopper with a bottom wall with at least one outlet opening in the bottom wall. A base receives the hopper and also has at least one outlet opening therein and a slot extending from a first end to a second end. A slide is slidably received in the slot of the base and also has at least one outlet opening therein. A loading tray can be provided which has a slot in which the base is received within the slot.
A rotatable knob or movable member is inserted into a second opening in the slide, wherein rotation of the knob results in a portion of the knob contacting the second opening of the slide, thus moving the slide with respect to the base and the hopper in a linear fashion to one of a fully opened and fully closed position. In a fully opened position, each outlet opening of the hopper, base and slide is in registry, allowing toner to flow out of the hopper to an image forming apparatus. In a fully closed position, each outlet opening of the slide is not in registry with the hopper and base openings, thus preventing toner flow out of the hopper.
The knob has a first surface having a handle and a second surface having an eccentric cam and an opening. A pin is inserted through a hole of the base and engages the opening of the knob. The eccentric cam engages the side wall of an opening of the slide to cause the slide to move with respect to the base. This slide opening can be rectangular or square. Labels can be provided on the slide to indicate the fully opened and fully closed positions.
The knob can have an eccentric cam and an axle, instead of a separate pin, where the axle engages the hole of the base. The knob can further have a plurality of teeth around an outside edge thereof. The slide can include an elongated opening with a plurality of teeth on an inner wall thereof. The teeth of the knob would matingly engage the teeth of the slide and rotation of the knob results in engagement of the teeth which in turn moves the slide with respect to the base. This rack and pinion arrangement allows a greater range of movement of the slide.
One advantage of the present invention is found in the provision of an indicator to the user that the cartridge is fully opened or closed.
Another advantage of the invention resides in the provision of a device for adding a mechanical advantage to the louvered slide mechanism for making it easier to open and close a cartridge.
Yet another advantage of the invention resides in the provision of a knob with a rack and pinion arrangement to provide a large range of movement.
Still other advantages and benefits of the invention will become apparent to those skilled in the art upon a reading and understanding of the following detailed description.